Connecting to Square

Square provides two different ways to connect:

• Via personal acess token -- to connect to your own data or test data through the sandbox.
• Via OAuth -- to connect to shared Square data over a browser.

Both of the above methods make use of OAuth functionality that is embedded in the CData Square driver.

Before You Connect

• Set the OAuthAccessToken connection property as described below, for the way you want to access data.
• Set the LocationId property to specify a default business location.

Personal Access Token

To connect to personal data, obtain your personal access token, then set the OAuthAccessToken connection property to that token:

1. Navigate to the Square Developer Dashboard at "https://developer.squareup.com/apps".
2. After the app is created, open the Credentials tab to find the personal token.

Square Sandbox

Version 2 of the Connect API permits you to test in a sandbox environment. Transactions created in the sandbox are not sent through to card networks, and cards are never charged.

To connect to the sandbox, obtain the sandbox access token, then set the OAuthAccessToken connection property to that token:

1. Navigate to the Square Developer Dashboard at "https://developer.squareup.com/apps".
2. After the app is created, open the Credentials tab to find the sandbox token.

OAuth

service; supports OAuth authentication only. To enable this authentication from all OAuth flows, you must set AuthScheme to OAuth.

The following subsections describe how to authenticate to Square from three common authentication flows:

• Desktop: a connection to a server on the user's local machine, frequently used for testing and prototyping. Authenticated via either embedded OAuth or custom OAuth.
• Web: access to data via a shared website. Authenticated via custom OAuth only.
• Headless Server: a dedicated computer that provides services to other computers and their users, which is configured to operate without a monitor and keyboard. Authenticated via embedded OAuth or custom OAuth.

For information about how to create a custom OAuth application, and why you might want to create one even for auth flows that have embedded OAuth credentials, see Creating a Custom OAuth Application.

For a complete list of connection string properties available in Square, see Connection.

Desktop Applications

CData provides an embedded OAuth application that simplifies authentication at the desktop. You can also authenticate from the desktop via a custom OAuth application, which you configure and register at the Square console. For further information, see Creating a Custom OAuth Application.

Before you connect, set the following variables:

• InitiateOAuth = GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
• Custom OAuth applications only:
  • OAuthClientId = the client Id assigned when you registered your custom OAuth application.
  • OAuthClientSecret = the client secret assigned when you registered your custom OAuth application.
  • CallbackURL = the redirect URI defined when you registered your custom OAuth application.

When you connect, the adapter opens Square's OAuth endpoint in your default browser. Log in and grant permissions to the application.

After you grant permissions to the application, the adapter completes the OAuth process:

1. The adapter obtains an access token from Square and uses it to request data.
2. The OAuth values are saved in the path specified in OAuthSettingsLocation. These values persist across connections.

When the access token expires, the adapter refreshes it automatically.

Web Applications

Authenticating via the Web requires you to create and register a custom OAuth application with Square, as described in Creating a Custom OAuth Application. You can then use the adapter to get and manage the OAuth token values.

This section describes how to get the OAuth access token, how to have the driver refresh the OAuth access token automatically, and how to refresh the OAuth access token manually.

Get the OAuth access token:

1. Set the following connection properties to obtain the OAuthAccessToken:
   • OAuthClientId = the client Id in your application settings.
   • OAuthClientSecret = the client secret in your application settings.

2. Call stored procedures to complete the OAuth exchange:
   • Call the GetOAuthAuthorizationURL stored procedure. Set the AuthMode input to WEB and the CallbackURL to the Redirect URI you specified in your application settings. The stored procedure returns the URL to the OAuth endpoint.
   • Navigate to the URL that the stored procedure returned in Step 1. Log in and authorize the web application. You are redirected back to the callback URL.
   • Call the GetOAuthAccessToken stored procedure. Set the AuthMode input to WEB. Set the Verifier input to the code parameter in the query string of the redirect URI.

After you obtain the access and refresh tokens, you can connect to data and refresh the OAuth access token automatically.

Automatic refresh of the OAuth access token:

To have the adapter automatically refresh the OAuth access token, do the following:

1. The first time you connect to data, set the following connection parameters:
   • InitiateOAuth = REFRESH.
   • OAuthClientId = the client Id in your application settings.
   • OAuthClientSecret = the client secret in your application settings.
   • OAuthAccessToken = the access token returned by GetOAuthAccessToken.
   • OAuthSettingsLocation = the path where you want the adapter to save the OAuth values, which persist across connections.
2. On subsequent data connections, set the following:
   • InitiateOAuth
   • OAuthSettingsLocation

Manual refresh of the OAuth Access Token:

The only value needed to manually refresh the OAUth access token is the OAuth refresh token.

1. To manually refresh the OAuthAccessToken after the ExpiresIn period (returned by GetOAuthAccessToken) has elapsed, call the GetOAuthAccessToken stored procedure.
2. Set the following connection properties:
   • OAuthClientId = the Client Id in your application settings.
   • OAuthClientSecret = the Client Secret in your application settings.

3. Call RefreshOAuthAccessToken with OAuthRefreshToken set to the OAuth refresh token returned by GetOAuthAccessToken.
4. After the new tokens have been retrieved, set the OAuthAccessToken property to the value returned by RefreshOAuthAccessToken. This opens a new connection.

Store the OAuth refresh token so that you can use it to manually refresh the OAuth access token after it has expired.

Headless Machines

If you need to log in to a resource that resides on a headless machine, you must authenticate on another device that has an internet browser. You can do this in either of the following ways:

• Option 1: Obtain the OAuthVerifier value.
• Option 2: Install the adapter on a machine with an internet browser and transfer the OAuth authentication values after you authenticate through the usual browser-based flow.

After you execute either Option 1 or Option 2, configure the driver to automatically refresh the access token on the headless machine.

Option 1: Obtaining and Exchanging a Verifier Code

To obtain a verifier code, you must authenticate at the OAuth authorization URL. Do the following:

1. Authenticate from the machine with an internet browser, and obtain the OAuthVerifier connection property.

   If you are using the embedded OAuth application, call the GetOAuthAuthorizationURL stored procedure. Open the URL returned by the stored procedure in a browser.

   If you are using a custom OAuth application, set the following properties:

   • InitiateOAuth = OFF.
   • OAuthClientId = the client Id assigned when you registered your application.
   • OAuthClientSecret = the client secret assigned when you registered your application.

2. Call the GetOAuthAuthorizationURL stored procedure. The stored procedure returns the CallbackURL established when the custom OAuth application was registered. (See Creating a Custom OAuth Application.)

   Copy this URL and paste it into a new browser tab.

3. Log in and grant permissions to the adapter. The OAuth application redirects you the redirect URI, with a parameter called code appended. Note the value of this parameter; you will need it later, to configure the OAuthVerifier connection property.

4. Exchange the OAuth verifier code for OAuth refresh and access tokens. On the headless machine, set the following connection properties to obtain the OAuth authentication values:

   • InitiateOAuth = REFRESH.
   • OAuthVerifier = the noted verifier code (the value of the code parameter in the redirect URI).
   • OAuthSettingsLocation = persist the encrypted OAuth authentication values to the specified file.
   • Custom OAuth applications only:
     • OAuthClientId = the client Id in your custom OAuth application settings.
     • OAuthClientSecret = the client secret in the custom OAuth application settings.

5. Test the connection to generate the OAuth settings file.

6. After you re-set the following properties, you are ready to connect:

   • InitiateOAuth = REFRESH.
   • OAuthSettingsLocation = the file containing the encrypted OAuth authentication values. To enable the automatic refreshing of the access token, be sure that this file gives read and write permissions to the adapter.
   • Custom OAuth applications only:
     • OAuthClientId = the client Id assigned when you registered your application.
     • OAuthClientSecret = the client secret assigned when you registered your application.

Option 2: Transferring OAuth Settings

Prior to connecting on a headless machine, you must install and create a connection with the driver on a device that supports an internet browser. Set the connection properties as described above in "Desktop Applications".

After completing the instructions in "Desktop Applications", the resulting authentication values are encrypted and written to the path specified by OAuthSettingsLocation. The default filename is OAuthSettings.txt.

Test the connection to generate the OAuth settings file, then copy the OAuth settings file to your headless machine.

To connect to data via the headless machine, set the following connection properties:

• InitiateOAuth = REFRESH
• OAuthSettingsLocation = the path to the OAuth settings file you copied from the machine with the browser. To enable automatic refreshing of the access token, ensure that this file gives read and write permissions to the adapter.
• Custom OAuth applications only:
  • OAuthClientId = the client Id assigned when you registered your custom OAuth application.
  • OAuthClientSecret = the client secret assigned when you registered your custom OAuth application.

Post-Authentication Options

After you authenticate to Square, you can retrieve the Locations table, then set the LocationId to confine your search criteria to a chosen location.